U.S. patent number 6,038,519 [Application Number 09/001,804] was granted by the patent office on 2000-03-14 for control board for controlling and monitoring usage of water.
This patent grant is currently assigned to Sloan Valve Company. Invention is credited to Jerome M. Gauthier, Mark J. Sippel, Nhon T. Vuong.
United States Patent |
6,038,519 |
Gauthier , et al. |
March 14, 2000 |
Control board for controlling and monitoring usage of water
Abstract
An apparatus and method for controlling plumbing fixtures
includes an electronic control board having a microprocessor that
accepts four inputs and produces four outputs. Inputs at other than
the microprocessor's operating voltage are converted thereto.
Outputs having different voltages are controlled by latching
relays. The control board can be used with a Smart Sink that
requires a sequenced hand washing. The control board can form a
node on a network that monitors and controls the functions of
multiple boards throughout a facility.
Inventors: |
Gauthier; Jerome M. (Roselle,
IL), Vuong; Nhon T. (Lombard, IL), Sippel; Mark J.
(Schaumburg, IL) |
Assignee: |
Sloan Valve Company (Franklin
Park, IL)
|
Family
ID: |
21697915 |
Appl.
No.: |
09/001,804 |
Filed: |
December 31, 1997 |
Current U.S.
Class: |
702/91; 307/18;
700/292 |
Current CPC
Class: |
E03C
1/05 (20130101) |
Current International
Class: |
E03C
1/05 (20060101); H03K 005/20 () |
Field of
Search: |
;327/333
;702/64,90,91,107,189
;364/528.17,528.18,528.19,528.2,528.21,528.27-528.32,528.33
;307/18,52,125-140 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Hoff; Marc S.
Assistant Examiner: Miller; Craig Steven
Attorney, Agent or Firm: Dorn, McEachran, Jambor &
Keating
Claims
We claim:
1. An electronic control board for supplying a control signal to a
controlled device in response to a detection signal created by a
sensor, comprising:
a microprocessor responsive to logic high and logic low inputs, the
logic high inputs being at a designated operating voltage;
an input jack connectable to the sensor for accepting a detection
signal from said sensor;
converter means connected to the microprocessor for converting the
detection signal to the operating voltage; and
switch means connected between the input jack and the converter
means and microprocessor for supplying the detection signal to one
of the microprocessor or the converter means, the switch means
supplying the detection signal to the microprocessor if the
detection signal is at or near the operating voltage, otherwise to
the converter means.
2. The control board of claim 1 further comprising an inverter
between both the converter means and switch means and the
microprocessor.
3. The control board of claim 2 wherein the inverter comprises an
inverting Schmitt trigger.
4. The control board of claim 1 wherein the switch means comprises
a first jumper connected to the input jack and the
microprocessor.
5. The control board of claim 4 wherein the switch means comprises
a second jumper connected to the input jack and the converter
means.
6. The control board of claim 1 wherein the converter means
comprises an opto-isolator which is supplied with the operating
voltage.
7. The control board of claim 1 further comprising a power supply
section supplying at least one on-board voltage, and a power
connector connectable to an external power supply for receiving at
least one off-board voltage from said external power supply.
8. The control board of claim 7 further comprising an output jack
connectable to a controlled device, the microprocessor being
capable of controlling the supply of an on-board voltage, an
off-board voltage or an on-off current path to the output jack.
9. The control board of claim 8 further comprising a latching relay
connected between the microprocessor and the output jack.
Description
BACKGROUND OF THE INVENTION
This invention relates to an apparatus and method for monitoring
and controlling usage of water. Various electrical controls for
plumbing fixtures are known in the art. Some examples are shown in
U.S. Pat. No. 5,060,323 and U.S. Pat. No. 5,031,258. These controls
typically employ water valves operated electrically by solenoids,
together with various types of switches for activating the
solenoids at desired times. The switches include pushbutton
switches, infrared sensors in reflective mode or break-beam mode
for determining when a user is present and when water should be
supplied.
One of the problems with prior art controls is their inherent lack
of flexibility. The controls can only perform one function with one
type of fixture. Yet there is a wide variety of plumbing fixtures
that need to be controlled, such as sinks (with temperature
controlled either by pre-set hot and cold water mixing or
user-selectable mixing), showers, urinals and water closets. It is
also sometimes desirable to control related apparatus such as soap
dispensers and towel dispensers. Existing controls cannot be used
with all of these different facilities, at least not without
substantial alteration of their basic functions to the point of
totally rebuilding the controls to suit a different device. Further
complications arise due to the fact that some controlled devices
(sinks, showers, soap dispensers) need to respond to the arrival or
presence of a user, while other devices (urinals, water closets)
need to be aware of the presence of a user but not operate until
the user leaves a target zone. Prior art controls are simply not
set up to operate multiple types of fixtures in the various modes
needed.
In many institutional settings it would also be desirable to allow
the operator of the facility to select particular operating
characteristics of an apparatus. For example, in dormitories and
barracks it might be useful to limit the length of time a shower
will operate. Correctional institutions may want to limit the
number of times a water closet may be flushed within a given time
window. Health care or food service operations may prefer a hand
washing apparatus which will assure proper hand washing procedure
by the restaurant employees or hospital personnel in order to
reduce the chance of contamination. Being able to choose these
limits would be highly useful in these settings and others but the
lack of flexibility in existing controls prevents it.
Another desirable feature of water usage controls is the ability to
monitor remotely what is going on at a particular fixture or at all
fixtures throughout a building or institution. A further desirable
feature would be to alter remotely how a particular fixture
operates. This requires communications capabilities that are not
found in existing controls.
SUMMARY OF THE INVENTION
The present invention is directed to a control board for plumbing
fixtures that can be used with a wide variety of fixtures. The
board has a microprocessor which is programmable from either a
stored program or downloaded instructions or a combination of
these. The microprocessor operates in any desired mode with
settings that are either predetermined or set individually as
desired. The settings establish a timing control for the controlled
device, be it a sink, shower, water closet or some combination of
these. The timing control includes a delay before activation, a run
time, a delay after activation, the counting of cycles within a
selected time window, and an imposed lockout or inhibit time if a
cycle count limit is exceeded.
The control board can operate either as a stand alone device or in
a computer network, in which case the board communicates via either
twisted pair or a power line with a central computer for monitoring
and control purposes. The board can control solenoid valves or the
like either directly or through auxiliary boards. Input jacks on
the control board can accept signals ranging from 1.3 VAC to 120
VAC and 1.3 VDC to 100 VDC. An opto-isolator can be used, if
necessary, to convert input voltages other than the one used by the
microprocessor. The output section of the board uses latching
relays to conserve power. Three different outputs can be provided,
depending on the needs of the controlled device. These outputs
include two different on-board voltages or an off-board voltage. A
switch closure can also be provided to govern operation of a
self-powered controlled device.
BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1-7 together comprise a circuit diagram of the 4IO board.
More specifically FIG. 1 is the power supply section of the
board.
FIG. 2 shows representative samples of the input and output
sections, only one of each being shown for clarity.
FIG. 3 shows the microprocessor and some auxiliary functions and
the output addressing chip. The circuits in FIGS. 2 and 3 are
joined at junctions V, W, X, Y and Z.
FIG. 4 shows the microprocessor, the EPROM and a portion of the
flash option.
FIG. 5 shows the off-board voltage connector and one of the jumpers
for selecting outputs.
FIG. 6 shows the PLT-21 communications option.
FIG. 7 shows the FTT-10A communications option.
FIG. 8 is a longitudinal section of a pushbutton switch used to
actuate a plumbing fixture.
FIG. 9 is a circuit diagram of a latching relay.
FIGS. 10 and 11 comprise a flowchart of the 4IO software.
FIG. 12 is a block diagram of the Smart Sink.
FIGS. 13 through 26 comprise a flowchart of the Programmed Water
Technologies network software.
FIG. 27 is the main menu screen of the network software.
FIG. 28 is the detail form of the network software showing the
devices in a particular room.
DETAILED DESCRIPTION OF THE INVENTION
The present invention encompasses a new control board that can be
used with plumbing fixtures such as sinks, showers, water closets,
urinals and combinations of these. The board can provide the
central control of a programmed scrub sink referred to herein as a
Smart Sink. The board can also provide network communications with
a central computer for monitoring and data logging plumbing
fixtures throughout a facility in a system referred to as
Programmed Water Technologies. The present description will deal
with these three major areas: the 4IO board, the Smart Sink and its
software, and the Programmed Water Technologies network
software.
I. The 4IO Board
A schematic diagram of the control board 10 of the present
invention is shown in FIGS. 1-7. This particular embodiment can
accept input from four sensors or switches and direct output to
four controlled devices. Due to this capability of handling four
inputs and outputs, it is referred to herein as a 4IO board. It
will be understood that different numbers of inputs and outputs
could be used within the scope of the present invention. A
description of the major components of the 4IO board follows.
A. Power Supply Section
The power supply section of the board is shown generally at 12 in
FIG. 1. An off-board transformer (not shown) will provide 24 VAC to
connector TB1. The transformer is somewhere upstream outside of the
4IO board. Typically it is connected to the 120 VAC power main of
the building. It could be a transformer that is supplying power to
one board or it could be a transformer supplying power to many
boards. Line 13 from TB1 is connected to one side FH3 of a fuse
holder. The other side FH1 of the fuse holder is connected to
output power line 14, which is marked 24 VAC. This output power
line 14 is connected to any other location on the circuit diagram
similarly marked 24 VAC. The fuse F2 in holder FH1, FH3 is a slow
blow, two-amp fuse that limits the power output on line 14.
Line 13 has filters indicated at inductor L5, capacitor C33 and
resistor R40, and inductor L1 and resistor R12. Then there is
another fuse F1 in microfuse holder FH2 to protect the 5-volt logic
circuit. Fuse F1 is a quick-blow fuse rated at two amps. The 24 VAC
goes through the second fuse F1 to a bridge rectifier D1 which
turns the 24 VAC into approximately 30 VDC on line 16. An LED D35
indicates the presence of the 30 VDC. A capacitor C6 charges up to
maintain a stable input. That is used as a reserve so if there is a
small brownout, or if the line 16 goes down, there is a small
reserve of power. The board can survive off this reserve for a
short period of time.
Line 16 feeds the 30 VDC to a 9-volt switcher U6 which allows
voltage up to 9 volts DC to go through to line 18. When voltage to
line 18 starts to exceed 9 VDC the switcher turns off. When the
voltage falls back below 9 volts the switcher turns back on. So the
switcher produces a pulsating 9 volts DC on line 18. A filter
comprising inductor L2 and resistors R18, R19 conditions the
voltage. The purpose of the 9-volt switcher U6 is to reduce the
voltage going through to a 5-volt regulator U7. If the circuit went
directly from 24 VAC through the bridge rectifier to the 5-volt
regulator, the 5-volt regulator would over-heat. Since the 9-volt
switcher is required anyway, that 9 volt power is supplied on
output line 20. Other locations on the circuit marked +9V are
connected to line 20. Among other things the 9 VDC is used to
activate the latching relays in the output section, as will be
explained below. A latching relay only needs a 10 millisecond pulse
to latch or unlatch. The switcher U6 is going to be on most of the
time so usually when the 9 VDC is needed it will be there. There is
also a capacitor C7 connected to line 18 to store up some power. In
the event that the switcher U6 happens to be off when relay
activation is called for, capacitor C7 will be able to supply the
short pulse needed to latch the relay.
The 9 VDC is supplied to the 5-volt regulator U7. The 5-volt
regulator takes the 9 VDC and drops it down to 5 VDC, which is the
operating voltage for the microprocessor and the rest of the logic
circuit. The 5 VDC is supplied on output line 22. Locations on the
circuit marked VCC are connected to line 22. Capacitor C21 is a
high pass filter.
Taken together the power section is capable of supplying 24 VAC on
line 14, 9 VDC on line 20 and 5 VDC on line 22.
B. Microprocessor
The functions of the 4IO board are controlled by a microprocessor
U12 (FIGS. 3 and 4). The microprocessor is preferably a neuron type
3150, such as a TMP N3150 BLAF from Echelon Corporation of Palo
Alto, Calif., although others may suffice. It is designed to run at
a specified operating voltage, in this case 5 VDC. The
microprocessor has an internal electrically erasable,
reprogrammable memory that will be referred to herein as the EE
section of the microprocessor. The EE section is non-volatile
memory, meaning that the information in the EE section will not be
lost even if the power goes out. The microprocessor has three
internal processors. One of these runs the 4IO software described
below. Another runs communications software that is provided with
the chip. The third processor runs software that translates
information between the first two processors.
The first processor runs a 4IO program stored in an EPROM U3 (FIG.
4). The program is burned it into the chip and therefore is fixed.
The EPROM communicates with the microprocessor through lines A0 to
A15 and D0 to D7.
The 4IO board has heads or connectors built into it to provide a
stuffing option that allows for an alternate embodiment called a
flash option. The stuffing option can receive the logic chips shown
generally at 24. When these chips are provided the regular EPROM U3
is replaced with a flash EPROM, also known as an EEPROM (for
electrically erasable programmable read only memory). When a flash
EPROM is used an operator can download new software and store it in
the flash EPROM. Thus, the entire program can be rewritten. With
the regular EPROM changing the software requires putting in a new
EPROM chip. The details of the 4IO software will be discussed
below.
It will be noted that several clean-up capacitors are used to clean
up the 5 volts that is being distributed throughout the chips.
Capacitors C8 and C17 (FIG. 4) form a high pass and a low pass
filter. Capacitors C15, C22, C26, C25, C27 serve as high pass
filters. In the event that the power drain upstream limits the
voltage, capacitor C8 will also serve as a small battery for the 5
VDC source.
C. Input Section
A description of the input section details will benefit from a
preliminary discussion of the various remote switches and sensors
that might be found on a controlled device, i.e., on a sink, shower
or water closet.
A commonly-used switch is an inductive pushbutton switch, as shown
at 19 in FIG. 8. The switch 19 has a cylindrical housing 21 which
has external threads for engaging a mounting nut 23 and a wall
flange 25. The housing is clamped to an appropriate fixed mounting
surface 27 by the nut 23 and wall flange 25. Typically the mounting
surface 27 will be a wall near the sink, water closet or shower or
it might be a part of the fixture itself. A washer 28 and spacer 29
assist the clamping action. The wall flange 25 retains a pushbutton
30 which is slidable through a central opening in flange 25. The
pushbutton abuts one end of a flanged filler tube 31. The other end
of tube 31 adjoins a T-shaped plunger 32, which is made of ferrous
metal. The plunger 32, filler tube 31 and pushbutton 30 are all
biased to the left of FIG. 8 by a spring 33. Spring 33 bears
against a packing 34 which is retained by a bushing 37. The bushing
is threaded to the housing 21. A proximity sensor 35 is mounted in
the packing 34. Three conductors 36A,B,C supplying 5 volts DC, a
return signal and a ground, respectively, are attached to the
proximity sensor 35 and run back to the 4IO board. When a user of
the controlled device pushes the pushbutton 30 it carries the
plunger 32 close to the sensor 35 and changes the magnetic field
adjacent the sensor. The altered magnetic field triggers a circuit
inside the sensor 35 which closes a circuit between lines 36A and
36B, thereby creating a 5 VDC return signal. The sensor is a
readily available item and itself forms no part of the present
invention.
It will be understood that while the pushbutton switch is commonly
used to indicate to the 4IO board a user's request for operation of
a plumbing fixture, other types of devices can also be used. For
example, infrared light sensors can be used to detect the presence
of a user. An infrared emitter and detector can be placed adjacent
one another and infrared light reflected back from, say, a user's
hands under a faucet, will trigger the detector. Or the emitter and
detector can be separated with the emitter focused on the detector.
When a user breaks the light beam between the emitter and detector
a signal is triggered. When greater distances between the 4IO board
and a switch are required, a reed switch and a 24 VAC supply and
signal may used, rather than the 5 VDC. Or a relay switch may be
used with 5 volts going in with the return line coming back. In
that case, instead of just a piece of ferrous metal in the housing,
there is a magnet. When the magnet comes close to the relay switch,
the relay switch makes a contact which then gives a 5 volt return
signal.
Other inputs to the microprocessor may involve monitoring the
activities of various components, rather than looking for remote
switch closures. For example, it may be desired to monitor a 16 VDC
motor or a 24 VAC solenoid to find out when they activate so some
action can be taken in response thereto.
The foregoing illustrates that the 4IO board must have the ability
to accept a wide variety of input signals. The input section that
provides that ability will now be described. The 4IO board
communicates with the various switches or sensors of a controlled
device through four RJ-11 style input jacks, one of which is shown
at J4 in FIG. 2. Jack J4 is connected by jumpers JP9 and JP10 to an
inverting Schmitt trigger U2A, either directly or through an
opto-isolator U1A. The Schmitt trigger is connected to an I/O port
of the microprocessor by line 26A as shown. The jumpers may have
shunt clips that simply connect selected pairs of pins to one
another.
Pin 1 of J4 is connected to the 24 VAC source as shown. If the
particular remote switch or sensor connected to J4 requires 24 VAC,
pin 1 of J4 supplies it. Naturally if the switch does not use 24
VAC (or has its own power supply), the cable plugged into jack J4
would not have a connection to pin 1.
Similarly, pin 2 of J4 is connected to the 5 VDC source as shown.
In the case of the pushbutton switch, conductor 36A will connect to
pin 2, providing the 5 VDC source to the pushbutton switch. If the
remote switch does not need 5 VDC, the cable plugged into jack J4
would not have a connection to pin 2.
Pin 3 of J4 is a first sensor return. In the case of the pushbutton
switch, pin 3 will connect to conductor 36B, providing the 5 VDC
return signal. Line 39 connects pin 3 of J4 to pin 2 of jumper
JP10.
Pin 4 of J4 is connected to a clock signal from 109 of the
microprocessor. In a pushbutton scenario, a clock signal is not
used. But there may be some type of remote sensor that either
requires a clocking pulse to tell it when to operate or while it is
operating it may need clock pulses. Pin 4 would provide those
pulses.
Pin 5 of J4 is a DC ground. In the case of the pushbutton switch,
pin 5 will connect to conductor 36C.
Pin 6 of J4 is a second sensor return signal. Again, in the case of
a pushbutton switch, the 5 volt return signal would come in pin 3
and pin 6 would not be used. Pin 6 would be used with an AC return
signal. Line 41 connects pin 6 to jumper JP9's pin 2.
The shunt clips of jumpers JP9 and JP10 are set in accordance with
the type of remote switch or device connected to jack J4. If the
remote switch connected to J4 provides a 5 VDC return on pin 3 of
J4, the pins 1 and 2 of JP10 are shorted, as are pins 1 and 2 of
JP9. In that case the return signal on pin 3 of J4 goes directly to
the input of Schmitt trigger U2A, bypassing the opto-isolator U1A.
Also, in the case of a 5 VDC return signal the opto-isolator input
pin K,A is grounded through JP9 pins 2 and 1. The reason why this
is done is if one side of the opto-isolator is left open it can
pick up some noise because it has the ability to look at
alternating current and it takes very little power to trigger it.
JP9 forcibly ties it down so it will not operate. In the meantime
input A,K of the opto-isolator U1A is just floating freely. So
nothing is going into the opto-isolator. Therefore, nothing is
going to come out and mess up the signal that is coming around it
from JP10.
If the remote switch connected to J4 provides a return on pin 3 of
J4 that is anything other than 5 VDC, the pins 2 and 3 of jumper
JP10 are shorted, sending the return signal to input A,K of the
opto-isolator U1A. The settings of jumper JP9 depend on the power
source for the remote switch or device. If the remote device has
its own power supply then the shunt clip is left entirely off of
jumper JP9. If the remote device uses the 5 VDC power from J4 pin
2, then jumper JP9 is set to pins 1 and 2 to provide a DC ground.
If the remote device uses the 24 VAC power from J4 pin 1, then
jumper JP9 is set to pins 2 and 3 to provide an AC neutral through
line 43.
When the opto-isolator receives an input on its ports A,K and K,A,
it sends an infrared signal inside the device. The infrared signal
closes an electrical connection between ports C and E. Because an
infrared light signal is used internally in the opto-isolator to
trigger the output, there is no physical electrical connection
between the input side (ports A,K & K,A) and the output side
(ports C & E). Thus, whatever pin C is hooked up to will be
sent as an output signal, regardless of what input triggered the
output. In the present invention port C is hooked up to 5 VDC. So
now, no matter what signal arrives on the input side of U1A, the
rest of the circuit sees it as a 5 VDC signal on line 38.
The opto-isolator would be used when the 4IO board is looking at a
voltage other than 5 VDC or if it looking at a voltage not supplied
from the board. For example, take the case of monitoring a solenoid
which operates at 24 VAC. Jumper JP10 is set to pins 2 and 3 and
the other jumper JP9 is set at pins 2 and 3 so that same signal can
be returned. Thus, the board is monitoring what is on J4 pin 3 but
not giving it any power. With this arrangement there is no concern
about having a common ground or common power supply; the board is
just tapping in to see what is happening with that particular
solenoid. When it activates or deactivates then the signal can be
modified, whatever it is, to a 5 VDC signal and the processor runs
off of this new signal. And then, of course, in software this
signal can be controlled to be on or off, or when it should
activate depending on when that signal comes in, or if it should
activate when the signal comes in.
Now there is a 5 VDC signal on line 38 going into the Schmitt
trigger U2A, whether that signal comes from the opto-isolator or
through jumper JP10. Because the opto-isolator is picking up AC, it
has the ability to generate AC noise on the line. To clean up the 5
volt signal as much as possible there is a filter C4, R11 to help
reduce that high frequency noise. The filtered 5 volt signal is
sent to the Schmitt trigger U2A which is part of the common
circuit.
As in most electronic logic circuits, the 4IO board uses inverted
logic. That is, the normal output state is a logic high. In
electronics when a line breaks, there is nothing there. Logically
that is considered a high by solid state electronics and a
microprocessor. Because in the rest of the line, there is always a
little bit of trickle back from the components, it will drive a
line high. To have a good, definite signal you really want the line
to drive low. With a low line it is known that a signal is
definitely there; there is no question about whether some voltage
is a signal or noise. Accordingly, the Schmitt trigger U2A is an
inverter. What the Schmitt trigger does is take a signal coming in
that is variable due to noise and capacitance in the line and when
the input signal reaches a certain point, the Schmitt trigger turns
on and produces a clean signal out in the form of a square wave. In
this case, U2A is an inverting Schmitt trigger so, when the input
signal goes high the output is a nice, square wave with logic low.
Whatever signal comes in the Schmitt trigger cleans it up and
produces the opposite on line 26A for the microprocessor.
Amplifier U5C is involved with driving LED D5. The LED cannot be
driven with the same signal sent to the microprocessor, because
doing so can draw too much power away and produce a very weird
signal. In this case, a low signal is used to indicate that
something was occurring. It is desired that the LED D5 turn on to
indicate the presence of a signal. Thus, the LED is working in
reverse of the logic used by the microprocessor. An amplifier USC
is used to increase the power enough to drive the LED D5 so it
turns on when a logic line goes low.
Power for LED D5 is derived from VCC as shown. When line 38 goes
high (indicating the presence of a signal), line 40 goes low.
Amplifier U5C drives line 42 low. The amplifier U5C just takes
whatever signal is on line 40 and gives more power to it. So, in
this case, the amplifier is amplifying a logic low so it is forcing
line 42 low. The power VCC is coming through the LED D5 and a
current limiting resistor R17 to try to bring this line 42 up. But
U5C wants to make it low so now you have an electronic battle which
will be won by U5C which can sink more than what resistor R17 can
supply because it is a current limiting resistor. So there is a
current path that flows to the ground of U5C and this turns the LED
D5 on.
When line 38 is low (indicating the absence of a return signal),
line 40 is high. Then amplifier U5C forces line 42 high. Now there
is a high voltage on both sides of LED D5, there is no current path
and LED D5 is off.
It will be understood that for clarity only one input jack J4 is
shown and described. In actuality the board has a plurality of
input jacks identical to J4. In the preferred case there are four,
although it could be a different number. Each input jack has the
same associated circuit elements as shown for jack J1, i.e., a pair
of jumpers, an opto-isolator, a Schmitt trigger, an LED driver and
associated components. Thus, input lines labeled J1, J2, J3 in FIG.
3 each connect to the same circuit as shown for input line 26A.
D. Output Section
The output section of the 4IO board faces the same general problem
of the input section, namely, a variety of different controlled
devices need to be accommodated. A common controlled device will be
a solenoid for actuating a water valve on a sink or shower. But the
controlled device might also be a solenoid-activated flush valve, a
motor for a soap or towel dispenser, or an auxiliary control board
for one of these. Different outputs are required for these
different devices so provision must be made for supplying and
controlling these outputs.
As in the case of the input section, the 4IO board has four RJ-11
style jacks for connection to the controlled devices. One of these
jacks is shown at J10, the others being similar. Briefly, pin 1 of
each output jack connects to a switched 5 VDC. Pin 2 is connectable
to an selectable power source. Pin 3 provides a switched selectable
power source. Pin 4 is not used. Pin 5 is the return for the
selectable power. Pin 6 is a DC ground. How these connections are
made will now be described.
A latching relay is associated with each output jack. One of these
relays connected to jack J10 is shown at K4. The internal circuit
of a latching relay is shown in FIG. 9. The relay is a double-pole,
double throw device having first and second contacts 44-1 and 44-2.
There are also two coils in the relay. Each coil is connected to a
power source, at the terminals labeled SET and RESET, and to a
ground, labeled GND1 for the SET coil and GND2 for the RESET coil.
The contacts 44-1 and 44-2 are pivotably and electrically connected
to common pins labeled COM1 and COM2. In what is designated the
"normal" or latched condition, the RESET coil is considered the
most recently activated coil and the contacts 44-1, 44-2 engage
pins NC1 and NC2, respectively, thereby making electrical paths
between NC1-COM1 and NC2-COM2. When the SET coil is activated it
pulls the contacts 44-1, 44-2 into engagement with pins NO1 and
NO2, respectively, thereby making electrical paths between NO1-COM1
and NO2-COM2. There is no spring or other device biasing the
contacts 44 one way or the other so the contacts remain in their
most recently activated state until the opposite coil activates to
move the contacts to the other set of poles.
Returning now to FIG. 2, the connections to one of the latching
relays K4 will be described, it being understood that the other
relays have the same components connected thereto. The SET and
RESET pins are connected to the 9 VDC source on lines 46 and 48,
respectively. Pins NC1 and NC2 are not used. COM1 is connected by
line 50 to pin 3 of output jack J10. Line 50 is also connected to
selectable power line AC4A. COM2 is connected by line 52 to pin 1
of jack J10. Line 52 also branches off to an LED D10 that turns on
when line 52 is active. NO1 is connected by line 54 to pin 3 of
jack J10. NO2 is connected to the 5 volt power source VCC. GND1
connects to amplifier U9B through line 56. Line 56 branches to the
9 VDC power supply through diode D26. GND2 similarly connects to
amplifier U9A through line 58 which branches to a 9 VDC power
supply through diode D25.
The diodes D25 and D26 are there to help with inductive spikes.
When there is a relay coil and it is turned on, the 5 volt line
will drain so fast through U9A it now will draw as much power as
possible. This drops line 58 so low that it could actually be lower
than ground. In which case, there would be a current path but since
diode D25 is not allowing power to go from +9 VDC to U9A, there
will not be any current. But again when you turn the relay off you
have an inductive spike going the other way. A low does not hurt
the board but a high inductive spike might. In the case of a high
inductive spike, a high rush of current is produced. So in this
case, it is drained to ground to get rid of it. This helps with
inductive spikes created by latching/unlatching of a relay.
The output of the microprocessor comes out of its ports IO0 through
IO3 (FIG. 3). Four lines coming out of these ports connect to an
addressing chip U10. U10 only allows one output to turn on
depending on the combination of lines IO0, IO1 and IO2. IO3 is an
enabler. It tells the chip when to work and when not to work. IO0,
IO1 and IO2 are going to represent a binary number. That binary
number specifies which output to turn on when the chip U10 is
enabled by IO3. Only one of the outputs from U10 is going to be
activated at a time. Thus, one of the eight amplifiers U9A through
U9H (only three of which are shown) is going to amplify the signal
from U10 to allow for a greater current path.
Typically, from U10, turned "on" output is going to be a logic
zero. When it is activated it is a logic zero. Otherwise it's a
logic high. The amplifier U9 is going to amplify that. So on all
the amplifiers except one there is normally going to be 5 volts
coming out of the amplifier. One amplifier is going to have a logic
low or logic zero. For example, if amplifier U9A is low, line 58 is
pulled low, completing a current path through the reset coil and
pin GND2 of relay K4 and causing contacts 44 to close on the NC1
and NC2 pins. The contacts will stay that way even when U9A and
GND2 go high and shut off the reset coil. The relay contacts will
not move until amplifier U9B goes low, taking line 56 and GND1 low
and providing a current path through the set coil. With the set
coil active the relay contacts 44 will be thrown to pins NO1 and
NO2. With NO1 connected to COM1, the selectable voltage on AC4A and
line 50 will be provided to line 54 and pin 3 of jack J10. At the
same time the connection of NO2 to COM2 places the 5 VDC source on
line 52 and pin 1 of jack J10. Once again the relay contacts will
remain in this position even when U9B goes high and removes current
from the set coil.
Since only one relay one coil is activated at a time and it is not
necessary to maintain the power, the power consumption of the 4IO
board is greatly reduced. For example, if the board is controlling
a shower and the shower is to be on for 10 minutes, the
microprocessor sends a 10 millisecond pulse to unlatch the relay
and turn the shower on. The relay is left there. The processor
comes back in 10 minutes, looks at its watch and says when 10
minutes expires, go to the other address to unlatch (reset) this
relay and turn the shower off.
The selectable voltage at AC4A is determined by two shunt clips on
a jumpers JP6 (FIG. 5). Keep in mind that there is one such jumper
for each of the four output jacks and each jumper and output jack
has its own selectable voltage line ACxA, where "x" can be 1,2,3 or
4. Each jumper, such as JP6 in FIG. 5, has on pin 1 a 24 VAC supply
from line 14 of the power supply section 12. Pin 2 connects to line
AC4A at line 50. Pin 3 connects to an external power source. Pin 4
is blank. Pin 5 is connected to ground for the external power
source. Pin 6 is the return line from AC4B on pin 5 of jack J10
(FIG. 2). And pin 7 is an AC neutral.
The external power source, also referred to as an off-board power
source, comes into the 4IO board at jack J5 in FIG. 5. J5 simply
provides pins for four external power sources and related grounds
therefor. These are connected to pins 3 and 5 of each of the output
jumpers JP6. Thus, if a controlled device requires a voltage other
than the 24 VAC or 5 VDC available from the 4IO board's power
section, that off-board voltage could be supplied to jack J5. One
jumper shunt clip on JP6 would be set to pins 2 and 3 so external
power would be provided on AC4A and thus on pin 2 of output jack
J10. Furthermore, a switched external power would be available on
pin 3 of J10. The other jumper shunt clip would be placed on pins 5
and 6 of JP6 to connect AC4B from pin 5 of J10 to external ground
at JP6 pin 5.
If the controlled device needs 24 VAC, the jumper JP6 shunt clips
are set on pins 1 and 2, and pins 6 and 7. That places 24 VAC on
AC4A and AC4B, which in turn are connected to pins 2 and 5 of
output jack J10. Also, a switched version of the 24 VAC source
would be available through COM1-NO1, line 54 and pin 3 of J10. If
the controlled device needs 5 VDC, that's going to always be
available at pin 1 of J10 (when K4 is unlatched), regardless of the
jumper JP6 settings.
It will also be noted that if the controlled device has its own
power supply but it is desired to switch that power supply (control
when the device turns on and off), pins 2 and 3 of J10 could be
tapped into the power circuit on the controlled device. Contacts
44-1 at the NO1 and COM1 pins would complete the power circuit when
the set coil of relay K4 is activated. Thus, the relay can simply
provide a switch closure. In this case the jumper shunt clips would
be removed from JP6 so nothing is supplied to AC4A or AC4B.
From the foregoing it can be seen that the microprocessor can
control the supply of different on-board voltages, or an-off board
voltage or just provide a switch closure to a controlled
device.
E. Communications and Utilities
The 4IO board has the ability to communicate through twisted pair
lines or a power line. The twisted pair communications module is
known as FTT-10A as is shown in FIG. 7. The power line module is
indicated as PLT-21 in FIG. 6. These are both stuffing options,
whichever one desired can be used. The FTT-10A can be bus or star
topology. It is just a matter of the type of communication package
desired. Other options such as RS485 might also be used. Both the
FTT-10A module and PLT-21 transceiver can be obtained from Echelon
Corporation of Palo Alto, Calif. The communication lines CP1, CP0
and CLK2 of the FTT-10A option and the PLT-21 option extend from
the microprocessor to the communications module. The microprocessor
sends out a series of 1's and 0's on each of these lines. The
transceiver is really a big transformer, an isolation transformer,
and it sends out those same clocking signals in serial fashion on
either line Data A or Data B (FIG. 7). The transceiver on the other
end looks at the two lines and when a difference is detected then
there must be communication. Then the receiver starts looking at
the combination of 1's and 0's to determine if it is a valid
message or not. This type of transmission is known as Manchester
differential encoding. Since signals are sent on Data A or Data B
polarity is not a concern. That is, the two wires can be hooked up
in either fashion.
The only difference with power line communication is there are more
communication lines hooked up and there is a little intelligence in
the chip that stores some of the information and then sends it out
at a slower rate. But essentially the same type of differential
Manchester encoding applies with the power line transceiver. The
transmission is slowed down a little bit and also it has the
intelligence to look at the power line to see if there is traffic
on the line or not.
The other components shown set up the voltage that is used for the
comparison by the transceiver. An inductor helps reduce noise
spikes and things like that and it is just cleaning up the
communication on a line.
Returning to FIG. 3, the 4IO board has a reset switch SW1. If
something goes drastically wrong or it is desired to start from a
known beginning the reset switch is pressed. It tells the processor
forget whatever you're doing, start from scratch. Start from the
very beginning of your program. It does not affect the EE section
of the microprocessor. It only tells the processor to stop what
you're doing and start from the very first step of your program.
That first step may be to turn all the relays off as a safety
precaution.
U11 is a chip that makes sure that the voltage is maintained. U11
is a chip that acts like a watchdog for the 5 VDC power. It makes
sure that the 5 VDC does not drop below 4.3 volts. It is a security
measure to make sure that the processor does not produce errors due
to low voltage. When the 5 VDC line drops below 4.3 volts U11 will
automatically tell the processor to reset. U11 will keep sending
that signal until the 5 VDC line is back above 4.3 volts. This chip
reset does the exact same thing as the push button reset SW1. It
just tells the processor to start from the beginning. As long as
that reset is held low, the processor is not going to work. It will
be in continual reset. If a processor is allowed to free wheel or
work on its own when the power drops below 3.8 or 3.7 volts, it
does not have enough power to latch information into its memory so
there may be some old information, some new information, or a
combination of old and new information. The processor is trying to
operate but the data is completely unreliable. You just do not know
what is in the processor's memory. U11 protects against that
happening.
The service switch SW2 is a special switch typically used in a
communication format. When the service switch is pressed it invokes
a special routine in the processor. It tells the processor to send
out its unique neuron ID number and to identify itself with that
unique neuron ID number. So it will make a message that says this
is my unique neuron ID number and it will throw it out on the
communication line. That's what that service switch does. Also
embedded in the software there is the ability through a combination
of reset and the service switch to go into what is called an
unconfigured state. Typically that is used when something is going
very wrong or something needs to be changed drastically or you need
this board not to work for some reason. You can force the board not
to work by going into an unconfigured state. That is usually used
as a diagnostic tool or if new information is going to be
downloaded that will take a long time.
J6 in FIG. 3 provides some extra input output points that can be
configured through programming to do pretty much whatever is
needed. Since they are not used in the circuit they were brought
out to a header with a 5 VDC power and 5 VDC ground so this can be
used at a future date. In most cases it is not being used. It is
for future expansion. In the case of the Smart Sink there is
another board attached to J6 that has three pushbuttons. Those
three pushbuttons interact with the software to talk to another
display to change parameters just like would be done through a
personal computer.
The 4IO board has a ground shield to eliminate radio emissions from
going in and out of the board. Internally there is foil that goes
around the entire board except where the traces go through. That
acts as a shield to help prevent radio emissions from affecting the
data lines externally because we have all these 1s and 0s running
back and forth. Naturally, that's going to cause noise. To prevent
it from radiating out to the world, an earth ground shield is
embedded in the board. That noise will tend to go to that earth
ground shield. So, the noise that we generate from our board is
going to be drained to ground and the noise from the outside world
is going to be drained to ground by the same shield.
F. 4IO Software
The software for use on the 4IO board is stored on the EPROM U3 and
runs on the microprocessor U12. FIGS. 10 and 11 illustrate a
flowchart for a preferred general program for use with a variety of
plumbing fixtures. The flowchart only shows the program steps for a
single input and output channel; it will be understood that the
steps for the other channels are similar.
The program begins at 55 by initializing a set of parameters for
each particular input and output channel. The parameters
include:
Valid target time--this is the length of time an input signal must
be present before the computer recognizes it as a valid input.
While the term "target" envisions an infrared sensor as the
activating device on the fixture, it also is meant to encompass the
actuation of a pushbutton switch or the like.
Activation type--this tells the computer whether it should act on a
valid target signal when the signal appears or after the signal
disappears. This is to accommodate fixtures such as water closets
that should not be activated until a target, i.e., the user, leaves
the fixture.
Delay before on time--this is the length of time the computer
should wait before activating an output after a valid target is
seen and the appropriate activation type is allowed for.
On time--the length of time the computer should allow activation of
the fixture. As explained above since the latching relays are used
to control the outputs, the on time is not synonymous with the
actual pulse length from the computer, which is very short. But if
left unlatched the relay can be allowed to provide an output for a
long time.
Delay after on time--this is the length of time, after activation
of the fixture, during which further inputs are ignored. This is to
give the fixture time to carry out its operation. Most commonly
this will be used with a water closet where it may take ten seconds
or so to complete a flush. During that time you don't want a new
flush request to interrupt an incomplete prior flush. So the delay
after on time is used to suppress new inputs following too closely
on a previous one.
Target count limit--in certain situations it is necessary to limit
the number of fixture operations within a certain window of time.
For example, if a request for flushing a water closet in a prison
cell is received more than twice in a five minute span it is likely
that an inmate is up to some mischief by issuing repeated flush
requests, i.e., hitting the flush button over and over. The target
count limit sets the maximum number of times a request will be
accepted within the window.
Window time--this is the length of time associated with the count
limit just described. When a first request is received a window
timer is started and a target count kept and checked to see if it
exceeds the specified limit. In the embodiment shown there is only
one window timer and it is not reset until it times out.
Alternately there could be multiple window timers with each target
starting an additional window so that the target limit is never
exceeded in any time frame, not just the one kept by a first timer.
Another way of handling the issue of multiple targets spanning the
end of a first window is to randomize the on delay and off delay
times. A longer off delay has somewhat the same effect as multiple
time windows.
Lockout time--the length of time an output is shut down if the
target count limit is violated. During the lockout time the
computer will acknowledge no inputs and provide no outputs. If the
4IO board is part of a PWT network the violation is reported to the
central computer.
User shut off permission--this parameter governs whether a second
switch or sensor activation by a user will turn off the fixture
prior to its run time limit. For example, can the user turn off the
shower before the ten minute time limit.
Randomize delays--this tells the computer whether it should use
fixed on/off delays or generate delays of random length.
Target count--this is the number of times that the pushbutton
switch or infrared sensor on a fixture has been actuated by a user.
It is ignored if a lockout is not used. It is initialized at zero,
incremented by each valid target and reset to one when the window
timer times out and to zero when the lockout timer times out.
Returning now to FIGS. 10 and 11, after initialization and junction
point A, the computer proceeds to monitor the input line for a
target at 57. When a target is seen (i.e., a pushbutton is pressed
or an infrared sensor is tripped), the computer waits at step 59 to
see if the target remains for the specified valid target time
before recognizing the target as valid. Once a valid target is
found the computer checks at 60 to see if target count limits are
imposed on this channel. If not it proceeds to junction point B,
with subsequent actions explained momentarily. If count limits are
in effect, the target count in incremented at 62 and checked at 64.
If this is a first target (i.e., we are not presently in a window
period), the window timer is started, 66, and the computer goes to
junction B. If this is not a first target, the computer checks at
68 to see if the previously set window has expired. If it has, a
new window is started and the target count is reset to one, as at
70. If the window is still in effect, the target count is compared
to the limit at 72. If the limit has not been exceeded we go to
junction B. But if the target count limit has been exceeded, the
computer shuts down operation of both the input and output on this
channel, starts a lockout timer, resets the window timer and resets
the target count, 74. Operation will resume only after the lockout
timer times out.
Following junction B, the computer checks if it is ok to actuate
the fixture upon presence of the user or if it is to wait until the
user leaves the fixture, 76. If this parameter is set to "Leaving"
the computer waits at 78 until the target is no longer seen. Next
the computer checks if there is an on delay, 80. If there is an on
delay, the computer checks to see if it a random delay, 82. If so
the computer determines a random delay at 84, otherwise it uses the
specified fixed delay to wait, 86, prior to activating the output.
Activation at step 88 involves a pulse to the appropriate latching
relay and starting an on timer. During the run or on time, the
computer will check at 90 if the user has shut off permission. If
so, the computer will look for a valid target or switch activation,
92, and shut off the output if it finds one. Otherwise the computer
simply watches the on timer at 94. With either expiration of the on
timer or a valid shut off request, the computer turns off the
output and resets the on timer, 96.
The computer next determines if there is an off delay, 98. If so,
any new pushbutton or sensor activations by the user are ignored
during the off delay time, 99. The off delay may be either fixed or
random as previously determined. Finally, the computer then returns
to junction point A and starts watching for the next target.
It can be seen that the basic control logic for an output is
delay-activate-delay within imposed cycle limits. This basic logic
suffices for a wide variety of applications but obviously it could
be changed through new software in the EPROM. For illustrative
purposes only, a specific example of the parameter settings in
shown in the following table. This example assumes the 4IO board is
connected to combination fixture having a sink with hot and cold
water on IO channels one and two, a water closet on IO channel
three and a shower on IO channel four.
______________________________________ Hot Cold Water Water Water
Closet Shower ______________________________________ Parameter: 1 2
3 4 Valid target time (millisecs) 100 100 100 1000 Activation on
present or leave P P L P Delay before on (seconds) 0 0 2 0 On time
(seconds) 20 10 3 600 Delay after on (seconds) 0 0 120 0 Cycle
count limit NO NO 2 NO Window time (seconds) 0 0 300 0 Lockout time
(seconds) 0 0 1800 0 User shut off permission? YES YES NO YES
Randomize delays? NO NO YES NO
______________________________________
It can be seen with the above setting the hot, cold and shower
water will be supplied without delays or cycle limits and the user
can shut them off. The water closet, however, can only be actuated
twice in five minutes and randomized delays will be supplied both
before and after activation, thus giving the flush valve time to
operate.
II. Smart Sink
A traditional hand washing apparatus will not always assure that a
proper hand washing sequence has been conducted. To activate the
traditional apparatus, the user will be required to physically
touch the fixtures at each station of the apparatus, such as the
faucet handle, soap dispenser lever or paper towel dispenser
handle. These fixtures might contain contaminants which can be
transferred to the user's hands. In addition, the careless user
might skip a step in the hand washing process or conduct a step
improperly to obtain proper hygiene, such as obtaining little or no
soap, or allowing an insufficient scrubbing time period.
The use of a programmed washing device was taught by Griffin, U.S.
Pat. No. No. 3,639,920. Griffin taught the use of a continuously
sequenced washing device in which water is discharged for a
predetermined interval, after which the water will be turned off
and the soap will be dispensed for another predetermined interval.
This is followed by a predetermined pause during which neither soap
nor water is dispensed. Thereafter, the flow of water is reinstated
and the flow continues until the user departs from the plumbing
fixture.
While a continuously sequenced washing device assures every step of
the washing cycle is conducted, the inflexibility of a continuously
sequenced washing device creates some additional problems. The user
is only allowed usage for a predetermined time interval at each
station. A user desiring a more extensive hand washing procedure is
not allowed the flexibility to remain at any one station for a
longer period of time than the predetermined time. Hence, a user
requiring more soap during the scrubbing period to conduct a proper
hand washing will not be allowed to do so. This inflexibility
prevents assurance that a proper scrubbing procedure was conducted.
In addition, a continuously sequenced washing device does not allow
the user to use only one particular station or vary the time
interval to better suit the particular situation.
The present invention overcomes the problems described above by
using a separate sensor for each of the three units in the
apparatus, namely, the faucet, soap dispenser and paper towel
dispenser. Each of these sensors are connected to the 4IO board.
The 4IO board can operate in either in a smart mode or a random
mode. The user may be provided with the option of selecting the
mode of operation through the use of a menu select switch. The user
may also have access to an override switch that bypasses the 4IO
board and turns the faucet on.
The smart mode allows a flexible, sequenced hand washing cycle. In
the smart mode, a proper hand washing procedure comprises a hand
wetting interval, then a dispensing of soap followed by a scrub
time interval, then a rinse time interval followed by a dryer
activation and, optionally, an output that verifies completion of a
proper hand washing sequence. The time for the scrub time interval
can be preprogrammed to suit the particular situation necessary for
obtaining a proper wash. During this scrubbing period, the user
will not be able to obtain water for rinsing off the soap, hence,
assuring that the user will not be able to continue without
conducting a proper scrub. Since separate sensors are used for each
station, the user is able to control the length of the wetting and
rinse intervals, as well as the number of dryer activations. Thus,
the user can obtain additional water (during wetting or rinse
only), soap or paper towel if additional water, soap or paper towel
are desired by the user. What the user cannot do is shorten the
scrub time and still obtain verification of a proper wash
sequence.
In smart mode the paper towel dispenser sensor is always active so
paper towel is always available. Also, if available, the override
switch could be used to force the faucet on for rinsing. Should the
user have an urgent need to interrupt the hand washing procedure,
the smart mode will allow the user to immediately dry his or her
hands. Obtaining paper towel out of sequence or activating the
override will preclude issuance of a verification of a proper wash
sequence but it will permit a user to meet an emergency without
soap covered hands.
To assist the user in the sequence of steps to be taken for
obtaining a proper hand wash, a display board is used to instruct
the user in the proper operation of the sink. The display board is
connected to the 4IO board via a communication link.
When the user wishes to use one of the washing stations
independently from the other stations, the user can select a random
mode. In the random mode, each sensor is active to allow each unit
to be used separately, without interaction among the stations.
The 4IO board will also have the ability to monitor the number of
times the faucet, soap dispenser and paper towel dispenser was
activated and, if desired, by whom. This data can then be retrieved
and logged to a central computer. It will be understood that the
software used by a 4IO board connected to a Smart Sink is different
from that shown in FIGS. 10 and 11.
Turning now to the details of the Smart Sink hand washing
apparatus, it comprises a wash basin (not shown) with a faucet
mounted thereon. Adjacent the basin are a soap dispenser and a
towel dispenser, both motor-driven to provide soap and towels at
the appropriate time. Each of the faucet and soap and towel
dispensers has a sensor associated therewith. A VFD/LCD display is
placed near the sink at a height where it will be easy to read.
Referring to FIG. 12, one electromechanical solenoid valve 152 is
mounted in the water supply line, after a pre-mixing device or back
check valves, to control the flow of water to the faucet. The valve
152 is off (closed) when no power is supplied to it and on (open)
when power is supplied to it. A faucet sensor 150 is mounted in the
vicinity of the faucet. A common arrangement is to have an infrared
emitter mounted in the neck or base of the faucet and aimed at a
point underneath the faucet outlet. An infrared detector is located
adjacent the emitter.
A faucet control board 148 contains a power supply, IR filter,
signal conditioner, and output driver. The board 148 also has a 24
VAC input from power supply 140. Power supply 140 is a transformer
for converting the line power 120 VAC to 24 VAC. Faucet control
board 148 generates a continuous pulse signal and sends it to the
faucet sensor 150. The emitter receives the pulse signal from the
faucet control board 148, and sends an infrared signal out to its
target zone. When a user places his or her hands underneath the
faucet, and therefore in the target zone of the emitter, infrared
light will be reflected off the hands to the detector, thereby
triggering a return signal to the faucet control board, which
processes the signal to determine if it is a valid target. If so,
the target is reported to the 4IO board through jack 122. The 4IO
board in turn may cause the faucet to turn on, depending on the
status of the 4IO software.
Mounted adjacent the basin is a soap dispenser having a motor
driven pump 158 for dispensing liquid soap. A soap dispenser sensor
156 is arranged so when a user places his or her hands under the
dispenser nozzle, soap will be pumped onto the user's hands. Soap
dispenser board 154 contains a power supply input, timing set up,
variable timer, variable motor driver and a soap priming circuit.
This circuit is controlled by the 4IO board 110. The circuit is on
when it receives a command from the 4IO board, otherwise it is off.
When the soap dispenser is on, it will supply power to the soap
dispenser sensor 156 and wait for the return signal. When the
target is valid, it will turn the soap pump on, and dispense soap
for a predetermined interval. The circuit also provides a prime
switch input.
Soap dispenser sensor 156 contains an IR emitter, IR detector, and
the supporting filter components. This sensor is arranged in the
break beam method. Peristaltic motor pump 158 will dispense soap
when power is supplied to it. When the prime switch 160 is pressed,
the pump 158 will operate. This function is used when an installer
needs to get the liquid soap to the nozzle quickly. It is normally
used at the time of filling the soap reservoir.
Also mounted near the basin is a towel dispenser which dispenses
paper towel or the like when rollers in the dispenser are actuated
by an electric motor 166. A paper towel dispenser sensor 164 can
activate the roller motor 166. Paper towel dispenser board 162
contains a power supply and a motor drive. The power supply
provides power to paper towel dispenser sensor 164 and waits for
the return signal to turn on the motor roller 166.
Paper towel dispenser sensor 164 contains IR emitter and detector,
filter, timing set up, and output driver. This sensor has an input
pin that receives the signal from the 4IO board's output jack 132
and activates the roller to dispense paper towel. A blow dryer
could be substituted for the towel dispenser.
The VFD/LCD display 138 has a driver board 134 which includes a
power supply (not shown) and an FTT communication link 136 for
talking to the 4IO board 110. Display driver board 134 will receive
data from a 4IO board 110, then send the data to display board 138
to display the message(s), and return the message back to the 4IO
board 110 for acknowledgement.
Overall control of the Smart Sink is governed by the 4IO board.
FIG. 12 shows schematically its main control circuit 112
(comprising primarily microprocessor U12 and EPROM U3), the twisted
pair (FTT) communication link 114, and an auxiliary I/O 116
(connector J6 on the 4IO board). Auxiliary I/O 116 has a total of
three auxiliary pins that can be configured to be inputs or
outputs.
The auxiliary I/O 116 can be connected to a menu select switch 142,
an increment switch 144 and a decrement switch 146. These three
switches together form a field input device which allows
alterations of the timing parameters used by the 4IO board. For
example, the menu select switch could be used to display the
required scrub time, and the increment and decrement switches could
be used to raise or lower that time. The field input device is
available only to the sink owner, not to users.
Every time the menu select switch 142 is pressed, a pulse is sent
to the 4IO board 110. It then sends a message out to the display
138, and by scrolling one message is displayed at a time on the
display. After selecting the desired changeable function through
the menu select switch, changing the function is accomplished
through the increment and decrement switches. Increment switch 144
sends a pulse to the auxiliary I/O 116 every time the increment
switch is pressed. The 4IO board 110 will increase the timing count
value and send this value out to the display. Similarly the
decrement switch 146 sends a pulse to the auxiliary I/O every time
the decrement switch is pressed. The 4IO board 110 will decrease
the timing count value and sends this value out to the display. For
example, to change the scrub time from 10 seconds to 15 seconds,
the owner's technician would first press the menu switch 142 until
the scrub time is displayed. The technician would then press the
increment switch 142 until 15 seconds is displayed on display 138.
Finally the technician would press the menu switch.
As described above the 4IO board 110 also consists of four input
connectors and four output jacks. Input jack 118 is connected to
the soap motor pump 158 and receives a feedback signal from the
soap motor pump 158 as to whether it has been activated. Similarly,
input jack 120 is connected to the paper towel dispenser motor
roller 166 and receives a feedback signal from the paper towel
dispenser as to whether it has been activated. Input jack 122 is
connected to the faucet control board 148 and receives a signal
from that board. The signal will go to the microprocessor which
determines when to turn on the faucet. Input jack 124 is not used
at this time although it might be used for sensing input from a
user's badge which is equipped with a radio transceiver.
Output jack 126 is connected to soap dispenser board 154 which
activates the soap dispenser motor pump 158. Output jack 128 is
connected through manual override 119 to solenoid valve 152. Output
jack 130 is connected to the Smart Badge electronic interface 153.
Output jack 132 is connected to the paper towel dispenser board
162.
A Smart Badge is a device worn by users that has a radio receiver
or transceiver and data recorder. When a valid hand washing
sequence is completed, output jack 130 is activated long enough for
the Smart Badge electronic interface 153 to send a radio signal to
a Smart Badge verifying a valid hand washing sequence. The Smart
Badge will record the fact of receiving the verification signal and
set itself to allow a user to pass other antennas or check points
in the facility.
FIG. 12 shows output jack 132 from the 4IO board to the paper towel
dispenser board 162 and the paper towel dispenser sensor 164. This
was done for the convenience of wiring up the system. The wires
from the sensor 164 are connected to the dispenser board 162 before
being connected to the 4IO board 110. Alternatively, the connection
from the 4IO board to the paper towel dispenser sensor 164 can be
directly tied together.
Manual override 119 consists of a rocker switch and a power supply
input. This rocker switch can be set to let the 4IO board assume
control of the solenoid valve 152 or to turn the solenoid valve 152
on regardless of the 4IO board's output. In normal operation, the
override switch 119 is set to allow the 4IO board to control the
valve. But the rocker switch can also be set to turn the solenoid
valve on regardless of the 4IO board's output.
The owner of the Smart Sink can choose whether to give a user
access to the manual override 119. Similarly, the owner can choose
whether to give a user access to the menu switch that will permit
selecting smart mode or random mode. It is contemplated that most
installations will provide access to the override switch but not
the menu switch. However, it depends on the owner's desires for a
particular facility.
When the smart mode is in effect, at the beginning of a wash cycle,
the message board 138 will display "Welcome to the Sloan Smart Sink
. . . Please Wet Your Hands". When hands are detected under the
faucet, the water is turned on for as long as the hands remain in
the target zone. Thereafter, the message on the message board will
be changed to "Please Get Some Soap". At this time, the soap
dispenser sensor 156 will be made active. The user then has the
option of getting more water or more soap. If the hands are not
detected by either the faucet or the soap dispenser with forty-five
seconds, the Smart Sink will restart at the beginning of the wash
cycle. If the hands are detected under the soap dispenser within
the forty-five seconds after the hands are no longer detected under
the faucet, the soap dispenser pump 156 will turn on to dispense a
premeasured amount of soap. The 4IO board will then turn off the
power to the water solenoid and disregard the faucet sensor.
The scrubbing time period is preprogrammed to suit the particular
situation. To assure proper scrubbing by the user, the faucet
sensor 150 will be disregarded and the water solenoid will be
deactivated during the scrubbing time interval such that no water
can be obtained during this period. The soap dispenser sensor 156
and paper towel sensor 164, however, do remain active. During the
scrubbing period, the message board 138 will display "Please Scrub
Hands For: . . ." the time remaining for the programmed scrubbing
time period, with the time counting down. If the hands are detected
again under the soap dispenser during the scrubbing period, an
additional premeasured amount of soap will be dispensed and the
timer will be reset for the entire programmed scrub time interval.
The message board will be changed correspondingly to reflect the
reset scrubbing time period.
After the scrubbing period is complete, the faucet will turn on,
off, on and then off in half second spurts. This signals the end of
the scrubbing period. Then the message on the display will change
to "Please Rinse Hands Off". At this time the user can get soap
again (which will cause the scrubbing sequence to be restarted) or
get water. If a choice is not made within forty-five second, the
Smart Sink will start at the beginning of the wash cycle. If the
hands are detected by the faucet sensor within the forty-five
seconds after the end of the scrubbing period, the water is turned
on for as long as the hands are detected.
When the hands are no longer detected under the faucet, a complete
hand washing has occurred. The complete hand washing is logged on
the 4IO board 110. The 4IO board sends a signal to the paper towel
sensor 164 via the paper towel dispenser board 162. This creates an
automatic paper dispense, a reward for completing a correct hand
washing. At the same time the 4IO board 110 sends a signal to the
Smart Badge electronics interface 153 (if attached) that a complete
hand washing has occurred. The Smart Badge electronics interface
will then send a verification of a complete hand washing to the
Smart Badge that the user is wearing. Also at the same time a
message is sent to the display board 134, "Please Take a Paper
Towel". If a paper towel dispense is not detected by the 4IO within
ten seconds, the Smart Sink will start at the beginning of the wash
cycle. If a paper towel dispense is detected by the 4IO board,
during the dispensing period, the display will show the message,
"Thank You And Have A Nice Day". Five seconds after the last paper
towel dispense, the Smart Sink will reset to the beginning of the
wash cycle.
The user can get paper towel at any time throughout the smart mode
hand wash operation. If the user takes a paper towel at any time
other than when he or she is instructed, an invalid hand washing
occurs and will be so noted by the 4IO board.
The other mode of operation the user may be permitted to select is
the random mode. When the Smart Sink is operating in the random
mode, all the control boards work independently of one another
within their own operating parameters and all the sensors for
detection in their respective sensing zones of control are
activated. When the random mode is selected, the message board will
display "Welcome to the Sloan Smart Sink ... Random Mode". The user
can obtain water, soap or paper towel in any order, for any length
of time.
III. Programmed Water Technologies
The purpose of the PWT Network Manager is to provide a means of
communication between a Lonmark compliant control board and a
computer. This software is used to monitor and/or change any
Lonmark compliant network variable. The PWT Network Manager allows
a computer to remotely install, replace, monitor, control, collect
and print data on Lonmark compliant control boards. The 4IO control
board is a Lonmark compliant control board.
A particular application of the PWT Network Manager software is in
correctional institutions. Such facilities typically have multiple
buildings, each with multiple floors and/or wings. Multiple rooms
or cells are usually located on each wing or floor. The cells may
have facilities such as a sink, water closet and possibly a shower.
These can be controlled as described above by a 4IO board. The PWT
software takes this concept a step further by permitting a remote
PC to monitor, log and control any and all fixtures throughout a
site. Each 4IO board becomes a node on a network that is managed by
the PWT front end software. The PWT software interacts with Lonmark
compliant boards. Lonmark is a trademark of Echelon Corporation and
refers to that company's method of packaging variables and
information in a known fashion so it can be sent across a network
and read by a receiving node.
The PWT Network Manager is unique because it allows Lonmark
compliant boards to send information that will be displayed on a
computer display. It also allows Lonmark compliant board
installation on a communicating network. The network can have up to
64,535 Lonmark compliant boards. Information can be bound or sent
from one board to another or from groups of boards to other boards.
The PWT software can interact with computers that use TCP/IP
protocol transceivers and the PWT Network Manager software.
The software can be set to one of three modes of operation; stand
alone, server, or client operation. In stand alone operation, a
personal computer (hereinafter "PC") can interact with Lonmark
compliant boards and one other PC via a phone modem connection. In
the server mode of operation, the central PC assumes that there is
at least one network card that can support TCP/IP protocol. The PC
in server mode can interact with other PCs that are running the PWT
Network Manager program in the client mode and are connected to the
same network. A server PC can also interact with one PC via a phone
modem connection and it can interact with multiple Lonmark
compliant boards. A PC in client operation assumes that there is a
network card that can support TCP/IP protocol. The PC can interact
with another PC that is running the PWT Network Manager program in
the server mode and is connected to the same PC network.
The PWT Network Manager software is described in the flow chart
shown in FIGS. 13-26. Looking first at FIG. 13, the software is
started at 200 and initially the system administrator should log in
to the system 202 and set up any user accounts. Once the system
administrator has set up the user accounts, each user can follow
the same login procedures to access the system. The privileges
associated with each user account will determine which system
features are available for that user. The user will be asked for
his or her password, 204, and the user's name and password are
checked to see if they are valid, 206. Several attempts at a valid
user name and password may be permitted. Once a valid user is found
the software and communication cards are initialized, 208 and
210.
The following steps are taken during the initialization process:
Opening the object server database (a database of graphics that
represent fixtures); opening and creating the network; installing
the local network variables; attaching to the NSI (the network
interface card in the central PC); setting up the NSS (the software
that has to do with communications to the NSI); creating a
supernode for application devices (a supernode is a node that
comprises more than one neuron chip, such as a Smart Sink that has
two neuron ID's--one on the 4IO board and one on the display
board); reading program templates; and completing the
initialization. The network includes a Paradox database and a
Lonworks database. Lonworks is a trademark of Echelon Corporation
for electronic circuits, integrated circuits, electronic circuit
boards, and electrical circuit components for a network which
provides identification, sensing, communications or control.
Paradox is a trademark of Borland International, Inc. of Scotts
Valley, Calif. for computer programs in the field of databases,
database application development, report generators and database
inquiry.
Initialization is checked for failure, 212. If the initialization
fails, a message is displayed 214 and the user is prompted to quit
or continue 216. If the user continues, any configuration changes
will be saved to the Paradox database but not to the Lonworks
database. The Paradox database contains information about the
number of buildings, floors, wings and rooms at a particular site.
The Lonworks database has an address table that associates neuron
ID's of particular 4IO boards (or other Lonmark compliant boards)
with particular rooms. This can be useful when configuring a site
prior to installation. In this scenario, the user could configure
the site without the Lonworks network and then use the
import/export feature to copy the Paradox database to disk and then
import into the system of the new site during installation. If the
user elects to quit, the application will be terminated, 218. If
the initialization is successful, the program continues with
junction box (the little pentagon) labeled A indicating that FIG.
13 joins with the similarly labeled junction box A on FIG. 14. The
software at 220 sets the program up to reflect the current user's
rights.
After logging onto the system, the PWT main menu form is displayed,
222. A diagram of the form is shown in FIG. 27. The form includes a
menu bar 201 and main section 203 which will be referred to as the
table view. The table view contains a visual representation of all
of the nodes on the network. To the right of the table view is the
table view filter 205. This filter allows the user to view only a
subset of the configured site.
The various menu options are available based on the user's
privileges. The file menu, network menu, report menu, options menu
and help menus will be further described below.
Each room on the table view will be displayed in either white, grey
or red. A grey room indicates that no devices have been assigned to
that room. A red room indicates that at least one of the devices
assigned to that room is in a violation state. A white room
indicates that none of the devices associated with that room is in
a violation state. Directly under the table view filter is a drop
down list of rooms in a violation state. Once a device goes into a
violation state, the room associated with that device is added to
this list. By selecting a room in this list or by clicking on a
white or red room in the main table view, a detail form of that
room will be displayed. An example is shown in FIG. 28. By
selecting OK from the detail form, the room will be removed from
the list until another violation in that room occurs. By selecting
cancel from the detail form, the room will remain in the list.
The detail form provides detail information for each of the devices
assigned to the room being displayed. Each configured output for
each device is displayed, up to eight outputs. The user may click
on a device output to select it. A blue box surrounds a currently
selected device output.
If the current device output can be activated, a bullet icon will
be displayed next to the device output. Clicking on the bullet icon
sends an activation notice to the device. Enable and disable push
buttons are provided to either enable or disable the currently
selected device output. The status for the currently selected
device is displayed in the lower left corner of the form.
The user can type room information in the box on the lower right
hand of the form. This information is stored for each room and
redisplayed each time the user enters the detail form. These notes
can be printed by choosing the print notes push button. To print
the entire form along with the notes, the print button can be
selected. Selecting the parameters button displays the timing
parameters form to modify the device output's timing
parameters.
The timing parameters include the delay before on time, the on time
and, the delay after on time as shown in the table above.
Selections can also be made for the lockout time, the cycle count
limit and the window time. Once the selections are made in the
timing parameters form, they are saved to become the new values for
the particular node.
Looking again at FIG. 27, the enable all nodes and disable all
nodes buttons 234, 236 at the bottom right corner of the form allow
the privileged user the ability to enable or disable all devices in
all the rooms currently displayed in the table view. Further
details will be described below.
Returning now to FIG. 14, the menu options are shown as file 224,
network 226, report 228, options 230 and help 232. If none of these
are selected, the program also looks for the enable all nodes
button at 234 or the disable all nodes button at 236 and the table
view filter 238. The drop down list of the rooms in the violation
state is shown at 240, with the option to enter a room at 242.
If the file menu is chosen, the program jumps to junction B shown
in FIG. 15. The options in this menu include log out 244. This
allows the user to log off of the system 246. No user privileges
will be allowed until the user logs back into the system by
selecting the file log in option 248. The change password option
250 will display a change password form 252 which asks for the
current password, the new password and confirmation of the new
password and includes a save button to allow the new password to
take effect.
The import/export option 254 allows the Paradox tables to be
imported into the Lonworks database and vice versa, 256. The
import/export form has the capability of deleting all data from
both the Paradox tables and the Lonworks database. You can also
import data from the Paradox database to the Lonworks database and
data can be exported from the Lonworks database to the Paradox
database. Both databases will be deleted before new data is
imported. The data includes the number of buildings, floors, wings,
cells and the details of the fixtures available in each cell.
The user setup option 258 brings up the user setup form 260 and
allows definition of the features a user will be allowed to use
within the system. It also allows users to be added or deleted or
have their privileges modified.
The daily password setup option 262 allows a daily password to be
assigned for each day of the year 264. This form also allows the
daily password feature to be turned on and off.
The backup data tables option 266 allows the data tables to be
copied to or from a diskette or from another directory, 268. This
is beneficial in configuring a system off site and later importing
the Paradox information into the Lonworks database.
The file menu also provides an exit option 270 which checks to see
if the user has the right to exit the program, 272. If the user has
that right the program closes all databases, terminates
communication with control boards, removes all personal rights from
the program, closes the program and returns to the PC's operating
system, 274 thus ending the program 276. If the program is not
exited it returns to junction A on FIG. 14.
The network options are shown at junction C in FIG. 16. The first
option is a variable monitor 278. This allows the user to select
and monitor specific network variables for a specific node, 280. In
addition, the user can select to log changes in these variables for
reporting purposes. The variable monitor puts up a monitor grid
which includes columns for a collect data field, the variable to be
monitored, the type of variable, the value of the variable, and the
direction. Variables added to the monitor grid continue to be
monitored until they are deleted from the monitor grid. Only
variables that are displayed in the monitor grid with a collect
data field of YES are logged in the data log for reporting
purposes. Data is only refreshed and logged while the variable
monitor form is opened. Data is automatically refreshed based on a
timer. The interval rate for the timer can be changed under the
options/refresh interval option. Logged data is automatically
purged based on the information provided under the options/purge
data log and alarm log option. Push buttons are available to add a
new variable to monitor in the monitor grid. There are also buttons
to delete a network variable from the monitor grid and to modify
the variable to change the value of the network variable. A
modification button is enabled only for input type variables. A
refresh button initiates the refresh of the network variables in
the monitor grid. In other words, this gets the network variable
value for each variable in the monitor grid. The variable monitor
form can be closed at which time variables can no longer be
refreshed or logged.
The site setup option 282 allows the configuration of the number of
buildings, floors, wings and rooms within the system, 284. The site
setup form includes fields for the site name, the number of
buildings in the site, the building number of the building
currently being configured, a building name associated with the
selected building number, the number of floors for the building
identified by the building name and number, the floor number of the
floor currently being configured, the floor name, the number of
wings, the wing number of the wing currently being configured, and
the wing name associated with the selected wing number. There are
also defaults that indicate whether there is more than one
building, floor, or wing in the system being generated. The site
setup form also includes fields for individual rooms. A room can be
added by typing a room name. A range of rooms can be added by
selecting a start and stop point of the range, the name prefix and
pressing the add button. Rooms can be removed by selecting a room
from the list box and pressing the delete key. A range of rooms can
be deleted by selecting the start and end range and pressing the
delete button next to the named prefix. The site setup form can be
cleared to start fresh with data entry. It can be restored to read
and display the site configuration last saved to the Paradox table.
A save button is supplied as is a cancel button.
The next option on the network menu is node maintenance 286 which
assigns specific nodes or control boards to a room 288. Devices can
be assigned to a room without providing a neuron ID prior to
installation. At installation time the find nodes feature can be
used to obtain the neuron IDs of the devices on the network and
then drop and drag these neuron ID onto the appropriate device.
Thus the site setup defines the buildings, floors, wings and rooms
in a site. And the node maintenance assigns a specific network
card, or in this case a 4IO card, to the defined rooms. The node
maintenance form includes a find button that waits for the service
switch SW2 in the 4IO board to be pressed. When that switch is
pressed the 4IO card sends its unique neuron ID number and tells
the PWT software which ID number is in which room. Once a device is
commissioned (assigned a neuron ID) it can be reset, tested or
taken on or off line.
The next option in the network menu is the variable binder 290.
This allows binding of specific network variables from one node to
another. That is, it identifies which information is going to be
passed from one board to the next, 292. A variable binding form
allows the user to add a hub node and network variable to the
connection list. It can also delete a hub node and network variable
from the connection list. Connection properties allow each
connection to be configured separately after selecting the hub node
and network variable from the connection list and selecting a
binding filter and network variable to bind. A connect button is
used to create a binding between these two nodes and network
variables. A disconnect button is provided to remove the binding
between two nodes and variables. The network menu option returns to
junction A1 on FIG. 14.
The report option is shown at junction D on FIG. 17. The variable
monitor report 294 will display a form that allows the user to
select which monitored/logged network variables to generate a
report from. The desired reporting variable is dropped in a column.
If desired a new label for the column and report header may be
typed in. The user selects print or view to generate a Reportsmith
report containing the selected variables 296.
The alarm report 298 presents all alarms by the system 300. The
report is sorted by computer date and node.
The site report 302 describes the site layout 304. The node report
306 describes the node layout 308. The variable binding report 310
describes the variable bindings between nodes 312. Any of the
selected reports are printed to the screen and/or hard copy at 314.
The PWT manager then returns to junction A1 on FIG. 14.
Selection of the options menu 230 causes the network manager to
branch to junction E in FIG. 18. The options menu will display a
device setup form 316 which will allow a device to be added,
described and associated with a Lonworks configuration file. It
will describe the board type, a variable list, how many inputs and
outputs the control board has and which bit map to assign to each
output. The option menu returns to junction A1 in FIG. 14. The
device setup form allows a user to modify, add or delete a device
type. To delete an existing device type, select the row of the
device to be deleted and press the delete key. To add a new device
type, simply enter the appropriate information in the blank row at
the bottom of the table. For each device type a unique ID is
created and a unique name should be given. This name will be used
for selecting the device type when creating a new node. Specify the
program template file associated with this device type. Next
identify the device type as a supernode (parent), child of a
supernode (child of device ID), or normal. Under IO count column,
indicate how many output devices are associated with this node (up
to four). Then identify each output type (toilet, shower, sink,
towel, soap, hot faucet of sink, cold faucet of sink). If the
program variables should be bound to the PC, specify YES in the
bind column, otherwise specify NO.
The help menu option 232 branches to junction box F in FIG. 19.
This will show help screens to describe the various windows and
controls, 318. The options on the help menu will include contents,
how to use help and a menu option which will display a form
indicating the version of the PWT Network Manager software. The
help options returns to junction A1 in FIG. 14.
The enable all water nodes push button 234 branches to junction box
G, FIG. 20. This will ask the user if the user really wants to
enable all outputs of the control boards in each of the rooms
displayed in the table view, 320. The user answers yes or no and
the program returns to junction A1.
A similar question is posed at junction H, FIG. 21 for the disable
all water nodes option. This option at 322 will shut down all the
boards shown on the main table view. Again, program control returns
to junction A1.
The table view filter 238 branches control to junction I, in FIG.
22. The table view filter allows the user to select a subset of the
configured site. The filter is saved by each computer and will be
reinitialized each time the application is started. The table view
filter can only be changed by users with the privilege to changing
the building, floor, wing and/or room filters. The filters include
the option to change the building 324 by picking one building from
a list or selecting all buildings, 326. The user can also select a
floor 328 by picking one floor or all of them, 330. Within each
floor, a wing can be chosen 332 by picking one wing or all wings
from a list, 334. Control returns to junction A1 on FIG. 14.
The new violation table 240 branches to junction box J, seen in
FIG. 23. If a violation has occurred in any of the rooms displayed
on the table view filter, that room number will appear in the main
screen and stay in the window until the operator has removed the
violation, 336. From this listing, a user can enter a room to view
its detail, 338. The detail of a room can be accessed either from
step 338 of FIG. 23 or from the enter a room selection 242 in the
main table view. Both of these paths connect to junction box K on
FIG. 24. The steps shown in FIG. 24 basically create the output
shown in the detail form of FIG. 28. At step 340 the status of the
control boards via bit maps and status strings is displayed. At
342, a blue box is placed around the output to manipulate. Options
are available at 344 and 346 to disable or enable all boards
assigned to that room, at 348 and 350. Option 352 allows the user
to disable just the output of the device that is surrounded by the
blue box 354.
The program continues at junction K1 on FIG. 25. At 356 the user
can enable the output surrounded by the blue box, 358. A push
button 360 is provided to change the parameters for the output the
blue box is around. As shown at 362, the delay before activation,
activation time delay, delay after activation, lockout time, target
limit and lockout length of time are all available to be altered at
this point. A print button 364 permits printing of all information
366. A print notes button 368 prints only a memo field.
The program continues at junction K2 on FIG. 26. The detail form
permits a user to change information in the notes or memo field
372. Any text information can be typed into the notes window 374.
Information is stored to the databases on the hard drive at 376.
The user is also given the option at 378 to return to the main
screen at junction A1 on FIG. 14 or go back to junction K in FIG.
24.
While a preferred form of the invention has been shown and
described, it will be realized that alterations and modifications
may be made thereto without departing from the scope of the
following claims.
* * * * *